An internal combustion engine typically includes a plurality of combustion cylinders in which are disposed a respective plurality of pistons. It is known to provide the pistons with a head end having a contoured surface on the side of the combustion chamber in an effort to improve combustion efficiency and reduce undesirable exhaust emissions. Incomplete combustion within the combustion cylinders due to poor fuel and air mixing results in generation of soot, carbon monoxide (CO) and hydrocarbon (HC) emissions. Hot zones in the combustion mixture result in the creation of nitrogen oxide (Nox) emissions which are also undesirable. In addition to improving combustion efficiency through the design of the piston crown and timing of the fuel/air mixture, other known methods of reducing emissions include exhaust after treatment and exhaust gas recirculation (EGR) systems.
Most of the larger internal combustion (IC) engines in use today have fuel injection rather than carbureted systems to provide the fuel/air mixture to the combustion cylinders. Each fuel injector includes an integral control valve and injector nozzle which are mounted at the head end of a corresponding combustion cylinder to inject fuel into the combustion cylinder. The injector nozzle is configured with a relatively high discharge rate to provide the fuel to the combustion cylinder in a single shot for mixing with the combustion air prior to combustion on the compression stroke of the piston. Although an injector system with single injectors for each combustion cylinder has been the norm for decades, improvements are still desirable to improve the combustion efficiency and reduce exhaust emissions.
What is needed in the art is a fuel injector system for an internal combustion engine which is reliable to use, improves combustion efficiency and reduces exhaust emissions.